package cn.xysfxy.fss.util;

import cn.xysfxy.fss.web.FileUploadListener;
import com.opensymphony.xwork2.inject.Inject;
import com.opensymphony.xwork2.util.logging.Logger;
import com.opensymphony.xwork2.util.logging.LoggerFactory;

import org.apache.commons.fileupload.FileItem;
import org.apache.commons.fileupload.FileUploadException;
import org.apache.commons.fileupload.RequestContext;
import org.apache.commons.fileupload.disk.DiskFileItem;
import org.apache.commons.fileupload.disk.DiskFileItemFactory;
import org.apache.commons.fileupload.servlet.ServletFileUpload;
import org.apache.struts2.StrutsConstants;

import javax.servlet.http.HttpServletRequest;

import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.io.UnsupportedEncodingException;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Enumeration;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import org.apache.struts2.dispatcher.multipart.MultiPartRequest;

public class MyMultipartRequest implements MultiPartRequest {
	static final Logger LOG = LoggerFactory.getLogger(MultiPartRequest.class);

	// maps parameter name -> List of FileItem objects
	protected Map<String, List<FileItem>> files = new HashMap<String, List<FileItem>>();

	// maps parameter name -> List of param values
	protected Map<String, List<String>> params = new HashMap<String, List<String>>();

	// any errors while processing this request
	protected List<String> errors = new ArrayList<String>();

	protected long maxSize;

	@Inject(StrutsConstants.STRUTS_MULTIPART_MAXSIZE)
	public void setMaxSize(String maxSize) {
		this.maxSize = Long.parseLong(maxSize);
	}

	/**
	 * Creates a new request wrapper to handle multi-part data using methods adapted
	 * from Jason Pell's multipart classes (see class description).
	 * 
	 * @param saveDir
	 *            the directory to save off the file
	 * @param request
	 *            the request containing the multipart
	 * @throws java.io.IOException
	 *             is thrown if encoding fails.
	 */
	public void parse(HttpServletRequest request, String saveDir) throws IOException {
		try {
			processUpload(request, saveDir);
		} catch (FileUploadException e) {
			LOG.warn("Unable to parse request", e);
			errors.add(e.getMessage());
		}
	}

	private void processUpload(HttpServletRequest request, String saveDir)
			throws FileUploadException, UnsupportedEncodingException {
		for (FileItem item : parseRequest(request, saveDir)) {
			if (LOG.isDebugEnabled()) {
				LOG.debug("Found item " + item.getFieldName());
			}
			if (item.isFormField()) {
				processNormalFormField(item, request.getCharacterEncoding());
			} else {
				processFileField(item);
			}
		}
	}

	private void processFileField(FileItem item) {
		LOG.debug("Item is a file upload");

		// Skip file uploads that don't have a file name - meaning that no file was
		// selected.
		if (item.getName() == null || item.getName().trim().length() < 1) {
			LOG.debug("No file has been uploaded for the field: " + item.getFieldName());
			return;
		}

		List<FileItem> values;
		if (files.get(item.getFieldName()) != null) {
			values = files.get(item.getFieldName());
		} else {
			values = new ArrayList<FileItem>();
		}

		values.add(item);
		files.put(item.getFieldName(), values);
	}

	private void processNormalFormField(FileItem item, String charset) throws UnsupportedEncodingException {
		LOG.debug("Item is a normal form field");
		List<String> values;
		if (params.get(item.getFieldName()) != null) {
			values = params.get(item.getFieldName());
		} else {
			values = new ArrayList<String>();
		}

		// note: see http://jira.opensymphony.com/browse/WW-633
		// basically, in some cases the charset may be null, so
		// we're just going to try to "other" method (no idea if this
		// will work)
		if (charset != null) {
			values.add(item.getString(charset));
		} else {
			values.add(item.getString());
		}
		params.put(item.getFieldName(), values);
	}

	private List<FileItem> parseRequest(HttpServletRequest servletRequest, String saveDir) throws FileUploadException {
		DiskFileItemFactory fac = createDiskFileItemFactory(saveDir);
		ServletFileUpload upload = new ServletFileUpload(fac);
		upload.setSizeMax(maxSize);
		/* 自己新建监听器 */
		FileUploadListener progressListener = new FileUploadListener(servletRequest);
		upload.setProgressListener(progressListener);// 添加自己的监听器

		return upload.parseRequest(createRequestContext(servletRequest));
	}

	private DiskFileItemFactory createDiskFileItemFactory(String saveDir) {
		DiskFileItemFactory fac = new DiskFileItemFactory();
		// Make sure that the data is written to file
		fac.setSizeThreshold(0);
		if (saveDir != null) {
			fac.setRepository(new File(saveDir));
		}
		return fac;
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.apache.struts2.dispatcher.multipart.MultiPartRequest#
	 * getFileParameterNames()
	 */
	public Enumeration<String> getFileParameterNames() {
		return Collections.enumeration(files.keySet());
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see
	 * org.apache.struts2.dispatcher.multipart.MultiPartRequest#getContentType(java.
	 * lang.String)
	 */
	public String[] getContentType(String fieldName) {
		List<FileItem> items = files.get(fieldName);

		if (items == null) {
			return null;
		}

		List<String> contentTypes = new ArrayList<String>(items.size());
		for (FileItem fileItem : items) {
			contentTypes.add(fileItem.getContentType());
		}

		return contentTypes.toArray(new String[contentTypes.size()]);
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see
	 * org.apache.struts2.dispatcher.multipart.MultiPartRequest#getFile(java.lang.
	 * String)
	 */
	public File[] getFile(String fieldName) {
		List<FileItem> items = files.get(fieldName);

		if (items == null) {
			return null;
		}

		List<File> fileList = new ArrayList<File>(items.size());
		for (FileItem fileItem : items) {
			File storeLocation = ((DiskFileItem) fileItem).getStoreLocation();
			if (fileItem.isInMemory() && storeLocation != null && !storeLocation.exists()) {
				try {
					storeLocation.createNewFile();
				} catch (IOException e) {
					if (LOG.isErrorEnabled()) {
						LOG.error("Cannot write uploaded empty file to disk: " + storeLocation.getAbsolutePath(), e);
					}
				}
			}
			fileList.add(storeLocation);
		}

		return fileList.toArray(new File[fileList.size()]);
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see
	 * org.apache.struts2.dispatcher.multipart.MultiPartRequest#getFileNames(java.
	 * lang.String)
	 */
	public String[] getFileNames(String fieldName) {
		List<FileItem> items = files.get(fieldName);

		if (items == null) {
			return null;
		}

		List<String> fileNames = new ArrayList<String>(items.size());
		for (FileItem fileItem : items) {
			fileNames.add(getCanonicalName(fileItem.getName()));
		}

		return fileNames.toArray(new String[fileNames.size()]);
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see
	 * org.apache.struts2.dispatcher.multipart.MultiPartRequest#getFilesystemName(
	 * java.lang.String)
	 */
	public String[] getFilesystemName(String fieldName) {
		List<FileItem> items = files.get(fieldName);

		if (items == null) {
			return null;
		}

		List<String> fileNames = new ArrayList<String>(items.size());
		for (FileItem fileItem : items) {
			fileNames.add(((DiskFileItem) fileItem).getStoreLocation().getName());
		}

		return fileNames.toArray(new String[fileNames.size()]);
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see
	 * org.apache.struts2.dispatcher.multipart.MultiPartRequest#getParameter(java.
	 * lang.String)
	 */
	public String getParameter(String name) {
		List<String> v = params.get(name);
		if (v != null && v.size() > 0) {
			return v.get(0);
		}

		return null;
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see
	 * org.apache.struts2.dispatcher.multipart.MultiPartRequest#getParameterNames()
	 */
	public Enumeration<String> getParameterNames() {
		return Collections.enumeration(params.keySet());
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see
	 * org.apache.struts2.dispatcher.multipart.MultiPartRequest#getParameterValues(
	 * java.lang.String)
	 */
	public String[] getParameterValues(String name) {
		List<String> v = params.get(name);
		if (v != null && v.size() > 0) {
			return v.toArray(new String[v.size()]);
		}

		return null;
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.apache.struts2.dispatcher.multipart.MultiPartRequest#getErrors()
	 */
	public List getErrors() {
		return errors;
	}

	/**
	 * Returns the canonical name of the given file.
	 * 
	 * @param filename
	 *            the given file
	 * @return the canonical name of the given file
	 */
	private String getCanonicalName(String filename) {
		int forwardSlash = filename.lastIndexOf("/");
		int backwardSlash = filename.lastIndexOf("\\");
		if (forwardSlash != -1 && forwardSlash > backwardSlash) {
			filename = filename.substring(forwardSlash + 1, filename.length());
		} else if (backwardSlash != -1 && backwardSlash >= forwardSlash) {
			filename = filename.substring(backwardSlash + 1, filename.length());
		}

		return filename;
	}

	/**
	 * Creates a RequestContext needed by Jakarta Commons Upload.
	 * 
	 * @param req
	 *            the request.
	 * @return a new request context.
	 */
	private RequestContext createRequestContext(final HttpServletRequest req) {
		return new RequestContext() {
			public String getCharacterEncoding() {
				return req.getCharacterEncoding();
			}

			public String getContentType() {
				return req.getContentType();
			}

			public int getContentLength() {
				return req.getContentLength();
			}

			public InputStream getInputStream() throws IOException {
				InputStream in = req.getInputStream();
				if (in == null) {
					throw new IOException("Missing content in the request");
				}
				return req.getInputStream();
			}
		};
	}

	public void cleanUp() {
		// TODO Auto-generated method stub

	}
}